Doing A means B says that if you do A then B happens.
So If I walk to the shop, I will be at the shop.
But, I cannot say that if I am at the shop, I must have walked there.
So
Doing A means B
&
Doing B means A
say different things, in general.
As an example, I could discount the cost of goods, so that would make the second sentence questionable, while the first sentence remains correct.